Black Panther 1,607 Posted February 9, 2014 Share Posted February 9, 2014 http://www.latimes.com/local/la-me-mari ... z2sYUMCc2I Link to post Share on other sites
DrWatson 381 Posted February 9, 2014 Share Posted February 9, 2014 As I've said for ages and ages, Copper, a first row transition metal, is a trace element and utilised by biology in serveral areas, including a number of important enzymes where it is a naturally employed cofactor.. It's not cadmium. It's not lead or tin. It's not mercury. It's not polonium. The target of 3ppb is VERY low. You'd find much more in your tap water if you have copper pipes. Infact... This from the EPA website: http://water.epa.gov/drink/contaminants ... copper.cfm The MCLG for copper is 1.3 mg/L or 1.3 ppm. EPA has set this level of protection based on the best available science to prevent potential health problems. And in Zürich the guideline is no more than 20 parts per billion... this is DRINKING WATER. Safe drinking water (EPA) is 300x more than the limit they want in their marina... This from the article: "Recent water quality analyses showed copper concentrations in Marina del Rey's water as high as 12 parts per billion, almost four times the regional board's standard of 3.1 parts per billion. Officials say it has the highest concentration of copper of any marina in California." It's not surprising that the copper is higher in the marina. but is it really that dangerous? But let's say the LAtimes article made a mistake and meant parts per million? well...it's still not that high, realistically and we're not drinking the marina water. and then this Like some locals, L.A. County also called for more detailed studies similar to one that was conducted in San Francisco Bay. In the Bay Area, further studies found the copper from some boats was less harmful than originally believed, leading officials to push for less stringent regulations. Let's see some serious science on the concentrations required to create biological problems here before we throw the baby out with the bathwater, and that should include a thorough cost/benefit analysis. Considering the increase of fouling on running costs (increased drag) and other environmental aspects like transmission of foreign greeblies into other environments. Seriously, do we go into a parking garage and say we'll all have to change to electric cars because the air in here is hard to breath? Link to post Share on other sites
Grinna 2 Posted February 10, 2014 Share Posted February 10, 2014 12 parts per billion is not high at all. There's been a bit of a concern with regards to copper, lead and zinc in estuarine sediments in the Auckland region (and elsewhere) lately and because of that Auckland Council have been trying to reduce the contaminants at the source .... i.e. colour steel roofing rather than simple galvanised iron, etc. Marina basins tend to have sediment settle out in them simply because they're a stilling basin ... a relatively quiet are of water that allows the suspended sediment to drop out of suspension and settle on the bottom. Fine sediment is also pretty good at grabbing and hanging onto metallic ions such as copper ions, so the sediments that collect in marina basins tend to have elevated concentrations of copper (and other metals). These sediments don't tend to change on a short term basis like water in the marina does (e.g. every tidal cycle). Sediments are therefore considered a more reliable measure of longer term contamination. There are guidelines for metals in sediments and water and the concentrations are set according to the likelihood for adverse biological effects as a result of the metals being considered. These guidelines have been arrived at by considering a whole bunch of international and local research into the effects of metals on various critters. The sediment quality guideline for copper for instance is 65 mg/kg dry weight (or 65 parts per million). Concentrations below this are pretty unlikely to result in any kind of adverse biological effects for the critters that live in those sediments. Between 65 ppm and 270 ppm there's an increased probability of adverse biological effects and at concentrations over 270 ppm adverse biological effects become likely to occur. These are guidelines .... not standards or rules ... just a guide. For seawater the situation for copper is a little more complex with trigger levels (which are even more woolly than guidelines). Trigger values of 0.3ppm for copper are protective of 99% of marine aquatic life, while 1.3 ppm is protective of 95%, 3 ppm is protective of 90% and 8 ppm is protective of 80% of marine aquatic life. A copper concentration in seawater of 1.3 ppm is thought to be typical of slightly to moderately disturbed ecosystems. So .... 12 parts per billion (0.012 ppm) of copper is not high at all. Link to post Share on other sites
wheels 543 Posted February 10, 2014 Share Posted February 10, 2014 So what about Copper (and other metals for that matter) that are naturally occuring in the ground. How does one know that these Metals are not naturally part of the Sea Floor sediment, especially in Auckland Sediments being so Volcanic? And with Testing, can it be determined if it is natural Copper or Copper from Antifoul? Which I guess if you could know, it would answer my first question. And what about all Aquatic species that are Hemocyanin. They need copper like we (and all warm blooded animals) need Iron. So why would Copper be so bad in the Sea sediment?? Link to post Share on other sites
Grinna 2 Posted February 10, 2014 Share Posted February 10, 2014 Great questions Wheels. There is a provision for local variations on metals concentrations based on natural background concentrations, however, the problem is identifying a "background" area that hasn't been modified to some degree. Places like the Coromandel are naturally highly mineralized and background concentrations of things like arsenic are above guideline values before you start adding anything from human activities. Most analyses are total metals .... That is they extract all of each individual metal from the sample regardless of the form it was in. You need to start spectating the metals concentrations .... working out what form the metals were in before you extracted it and then you can make intelligent guesses about where it's come from and you know how much of the more toxic forms of metals are present. The problem with that is that not many labs do that sort of analysis on a regular basis and the costs for doing it start to escalate alarmingly quite rapidly. So most agencies only deal in total metals concentrations (it's easier for them to wrap their heads around too). Link to post Share on other sites
Guest Posted February 10, 2014 Share Posted February 10, 2014 Losing Copper for antifoulings might be the best thing to happen for boaties. Believe it nor not 2 things will happen... 1. New technologies ( already in testing) will replace copper... and perform well. 2. Regulators will start panicking and reverse the ban when alternative practices / cleaning techniques create differing or larger issues. Just remember then huge pollution and costs dirty bottoms cost... and who pay (especially in the commercial world) Trust me the chemists are well ahead of thus and have many alternatives if copper vanished. Link to post Share on other sites
wheels 543 Posted February 10, 2014 Share Posted February 10, 2014 The problem with that is that not many labs do that sort of analysis on a regular basis and the costs for doing it start to escalate alarmingly quite rapidly. So most agencies only deal in total metals concentrations (it's easier for them to wrap their heads around too). So, using inaccurate measurements, they make inaccurate assumptions and ban something that is likely helping the prevention of Invasive Marine Species from being spread through out the country. Oh well, at least at the moment BP's link is for the "State of California" where virtually everything is either banned or could cause Cancer. I have decided it is best not to go to California and I should therefore be safe. 1. New technologies ( already in testing) will replace copper... and perform well. There are already alternatives available and have been for a few years now. But the alternatives are hugely expensive and unlikely to become cheaper, as the materials the alternatives are made from have been used in Industry for years. It's not like the old saying of, "it will get cheaper as more is made and sold". Link to post Share on other sites
Grinna 2 Posted February 10, 2014 Share Posted February 10, 2014 Elevated copper concentrations in sediments are bad because the critters that live in the sediment like worms and little shrimps and things are constantly exposed to the contaminant throughout their entire adult stage. Link to post Share on other sites
wheels 543 Posted February 10, 2014 Share Posted February 10, 2014 But at least thy wouldn't have Marine growth on them Link to post Share on other sites
Adrianp 120 Posted February 10, 2014 Share Posted February 10, 2014 Just remember then huge pollution and costs dirty bottoms cost... and who pay (especially in the commercial world) Thames Coromandel District Council reported that two lots of Mediterranean Fan Worm has been found in Coromandel Harbour. I wonder what impact it could have on the marine farms? Link to post Share on other sites
wheels 543 Posted February 11, 2014 Share Posted February 11, 2014 They can see something in the water in Coromandel Harbour? Link to post Share on other sites
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